Techniques of blood purification via extracorporeal therapy or transfusion related products are reliant on the hemocompatibility of materials used. CytoSorbents has been developing porous polymers for the removal of drugs and proteins for about 11 years. The development of biocompatible, highly porous polymer beads that can remove substances from blood and physiologic fluids is the core technology. Its flagship product is CytoSorb™, a highly efficient porous bead-based cytokine filter currently in human clinical trials to treat cytokine storm in patients with sepsis and severe lung injury. Blood is pumped out of the body, directly through a CytoSorb hemoperfusion cartridge where the beads remove cytokines broadly, and the purified blood is then pumped back into the body. CytoSorb has been used safely in more than 600 human blood treatments. The polymer beads have passed strict ISO 10993 biocompatibility and hemocompatibility testing, which also includes genotoxicity, acute sensitivity, cytotoxicity and others.
Most commercial porous resins are synthesized either by macroreticular synthesis (Meitzner, et al., U.S. Pat. No. 4,224,415; 1980), such as Amberlite XAD-4® and Amberlite XAD-16® by Rohm and Haas Company or by hypercrosslinking synthesis [Davankov, et al. J. Polymer Science, Symposium No. 47, 95-101 (1974)], used to make the Hpersol-Macronet® resins by Purolite Corp. Many conventional polymeric sorbents have a large pore surface and sorbtion capacity but are not hemocompatible and therefore are not suitable for sorbtion of proteins directly from body fluids.
The porous polymeric sorbents specified in the present invention demonstrate compositions and methods useful in selectively modifying the internal and external surfaces of porous polymer beads used in blood, blood product, or physiologic fluid purification. This methodology is useful in preserving or imparting hemocompatibility while allowing enhanced binding (or destruction) of protein toxins and pathogens.